1. Field of the Invention
The invention relates to the field of carrier lock closing apparatus. More particularly, the invention relates to an apparatus for closing a carrier which has been wrapped around one or more articles by forcing a larger tab through a smaller opening. In still greater particularity, the invention relates to a finger mechanism which is urged into contact with the tab thereby forcing the tab through the opening. By way of further characterization, but not by way of limitation thereto, the invention relates to a finger which may be cam operated or electromagnetically directed into said tab.
2. Description of the Prior Art
Carriers for transporting beverage containers such as those containing beer or soda have long been utilized in the beverage industry. Generally, these carriers are of a paperboard construction. Paperboard allows the carrier to be flexible yet strong enough to support relatively heavy loads. In addition, paperboard allows the packager to include advertising on the outside of the carrier. The use of paperboard carriers requires that the carrier be secured around the article or articles. Various locking mechanisms have been employed to secure the carriers around the articles. One such locking device is shown in U.S. Pat. No. 4,437,606 issued to Manville Service Corporation, the Assignee of the present invention. This patent is made a part of the specification hereof and incorporated herein by reference. Generally, this locking mechanism includes a tab and an opening. The tab is larger than the opening and is forced through the opening thereby locking the carrier around the articles.
One prior art device for inserting the tab through the opeining is shown in FIG. 3. Referring to FIG. 3, fingers 301 are spaced apart a predetermined distance and fixedly attached to a rotating shaft 302. The predetermined distance is based on the speed of the carrier 303 as it is transported on a conveying means 304 and the distance between the tabs to be locked. More specifically, carrier 303 is wrapped about articles 305 and transported past rotating shaft 302. As carrier 303 passes by rotating shaft 302 the speed of shaft 302 is such that fingers 301 are brought to the point generally designated at 306 in phantom at the top of rotating shaft 302. As such, fingers 301 extend above the plane of the conveying apparatus 304 and thus contact the tabs of the locking apparatus thereby pushing them through the opening.
The prior art device suffers from a disadvantage in that there is a relatively long period of contact between fingers 301 and the carrier. That is, fingers 301 begin to extend above the plane of the conveying apparatus 304 at point 307 reaching their maximum penetration through the plane of conveying apparatus 304 at point 306. Thereafter the fingers drop back through the plane of the conveying apparatus 304 at point 308. Thus, it takes rotation of approximately 35.degree. or more of the shaft 302 for fingers 301 to go from point 307 to point 308. Thus, fingers 301 are in contact with carrier 303 during the entire time and for the entire distance it takes for carrier 303 to move from point 307 to point 308. The result is that fingers 301 contact carrier 303 both before and after the tab is forced through the opening. The result is as shown in FIG. 4. That is, referring to FIG. 4, slight tearing of the paperboard at points 401 and 401 may occur as tab 403 is forced through opening 404. This tearing occurs because of the contact of fingers 301 both prior to, and after, reaching point 306 where the tab is forced through the opening. This contact by finger 301 on the carrier causes tearing on either side of opening 404 as the finger contacts the surface of the paperboard. This tearing results in a weakened lock and a weakened carrier.